FileSystemObject 示例代码

在本节描述的示例代码，提供真实的例子来示范在 FileSystemObject 对象模式中可用的许多功能。该代码显示了如何一起使用对象模式的所有功能，以及如何在您自己的代码中有效地使用这些功能。

请注意，由于该代码是极一般的，所以要使该代码能够真正在您的机器上运行，可能需要一些其他代码和小小的变更。这些改变之所以必要，是因为在 Active Server Pages 和 Windows Scripting Host 之间，为输入和输出给用户采用了不同的方法。

要在 Active Server Pages 上运行该代码，则采取以下步骤：

创建一个标准的 Web 页，后缀名为 .asp。

把下面的示例代码复制到 &ltBODY>...</BODY> 标记之间的文件中。

把所有代码包装器到 <%...%> 标记内。

把 Option Explicit 语句从当前位置移动到 HTML 页的最顶部，甚至在 <HTML> 开始标记前。

把 <%...%> 标记放置在 Option Explicit 语句周围，以保证它在服务器端运行。

把下面的代码添加到示例代码末尾： 

Sub Print(x)
   Response.Write "<PRE>&ltFONT FACE=""宋体"" SIZE=""1"">"
   Response.Write x
   Response.Write "</FONT></PRE>"
End Sub
Main

前面的代码增加一个将在服务器端运行，但在客户端显示结果的打印过程。要在 Windows Scripting Host 上运行该代码，则把下面的代码添加到示例代码的末尾： 

Sub Print(x)
   WScript.Echo x
End Sub
Main

下面就是示例代码：

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' FileSystemObject 示例代码
'Copyright 1998  Microsoft Corporation。   保留所有权利。 
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Option Explicit

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' 对于代码质量：
' 1) 下面的代码有许多字符串操作，用"&"运算符来把短字符串连接在一起。由于
'    字符串连接是费时的，所以这是一种低效率的写代码方法。无论如何，它是
'    一种非常好维护的写代码方法，并且在这儿使用了这种方法，因为该程序执行
'    大量的磁盘操作，而磁盘操作比连接字符串所需的内存操作要慢得多。
'    记住这是示范代码，而不是产品代码。
'
' 2) 使用了 "Option Explicit"，因为访问声明过的变量，比访问未声明的变量要
'    稍微快一些。它还能阻止在代码中发生错误，例如，把 DriveTypeCDROM 误拼
'    成了 DriveTypeCDORM 。
'
' 3) 为了使代码更可读，该代码中没有错误处理。虽然采取了防范措施，来保证代码
'    在普通情况下没有错误，但文件系统是不可预知的。在产品代码中，使用
'    On Error Resume Next 和 Err 对象来捕获可能发生的错误。
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' 一些容易取得的全局变量
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Dim TabStop
Dim NewLine

Const TestDrive = "C"
Const TestFilePath = "C:\Test"

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' 由 Drive.DriveType 返回的常数
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Const DriveTypeRemovable = 1
Const DriveTypeFixed = 2
Const DriveTypeNetwork = 3
Const DriveTypeCDROM = 4
Const DriveTypeRAMDisk = 5

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' 由 File.Attributes 返回的常数
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Const FileAttrNormal  = 0
Const FileAttrReadOnly = 1
Const FileAttrHidden = 2
Const FileAttrSystem = 4
Const FileAttrVolume = 8
Const FileAttrDirectory = 16
Const FileAttrArchive = 32 
Const FileAttrAlias = 64
Const FileAttrCompressed = 128

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' 用来打开文件的常数
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Const OpenFileForReading = 1 
Const OpenFileForWriting = 2 
Const OpenFileForAppending = 8 

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' ShowDriveType
' 目的： 
' 生成一个字符串，来描述给定 Drive 对象的驱动器类型。
' 示范下面的内容
' - Drive.DriveType
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Function ShowDriveType(Drive)

   Dim S
   
   Select Case Drive.DriveType
   Case DriveTypeRemovable
      S = "Removable"
   Case DriveTypeFixed
      S = "Fixed"
   Case DriveTypeNetwork
      S = "Network"
   Case DriveTypeCDROM
      S = "CD-ROM"
   Case DriveTypeRAMDisk
      S = "RAM Disk"
   Case Else
      S = "Unknown"
   End Select

   ShowDriveType = S

End Function

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' ShowFileAttr
' 目的： 
' 生成一个字符串，来描述文件或文件夹的属性。
' 示范下面的内容
' - File.Attributes
' - Folder.Attributes
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Function ShowFileAttr(File) ' File 可以是文件或文件夹

   Dim S
   Dim Attr
   
   Attr = File.Attributes

   If Attr = 0 Then
      ShowFileAttr = "Normal"
      Exit Function
   End If

   If Attr And FileAttrDirectory  Then S = S & "Directory "
   If Attr And FileAttrReadOnly   Then S = S & "Read-Only "
   If Attr And FileAttrHidden     Then S = S & "Hidden "
   If Attr And FileAttrSystem     Then S = S & "System "
   If Attr And FileAttrVolume     Then S = S & "Volume "
   If Attr And FileAttrArchive    Then S = S & "Archive "
   If Attr And FileAttrAlias      Then S = S & "Alias "
   If Attr And FileAttrCompressed Then S = S & "Compressed "

   ShowFileAttr = S

End Function

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' GenerateDriveInformation
' 目的： 
' 生成一个字符串，来描述可用驱动器的当前状态。
' 示范下面的内容
'  - FileSystemObject.Drives 
'  - Iterating the Drives collection
'  - Drives.Count
'  - Drive.AvailableSpace
'  - Drive.DriveLetter
'  - Drive.DriveType
'  - Drive.FileSystem
'  - Drive.FreeSpace
'  - Drive.IsReady
'  - Drive.Path
'  - Drive.SerialNumber
'  - Drive.ShareName
'  - Drive.TotalSize
'  - Drive.VolumeName
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Function GenerateDriveInformation(FSO)

   Dim Drives
   Dim Drive
   Dim S

   Set Drives = FSO.Drives
   S = "Number of drives:" & TabStop & Drives.Count & NewLine & NewLine

   ' 构造报告的第一行。
   S = S & String(2, TabStop) & "Drive" 
   S = S & String(3, TabStop) & "File" 
   S = S & TabStop & "Total"
   S = S & TabStop & "Free"
   S = S & TabStop & "Available" 
   S = S & TabStop & "Serial" & NewLine

   ' 构造报告的第二行。
   S = S & "Letter"
   S = S & TabStop & "Path"
   S = S & TabStop & "Type"
   S = S & TabStop & "Ready?"
   S = S & TabStop & "Name"
   S = S & TabStop & "System"
   S = S & TabStop & "Space"
   S = S & TabStop & "Space"
   S = S & TabStop & "Space"
   S = S & TabStop & "Number" & NewLine   

   ' 分隔行。
   S = S & String(105, "-") & NewLine

   For Each Drive In Drives
      S = S & Drive.DriveLetter
      S = S & TabStop & Drive.Path
      S = S & TabStop & ShowDriveType(Drive)
      S = S & TabStop & Drive.IsReady

      If Drive.IsReady Then
         If DriveTypeNetwork = Drive.DriveType Then
            S = S & TabStop & Drive.ShareName 
         Else
            S = S & TabStop & Drive.VolumeName 
         End If    
         S = S & TabStop & Drive.FileSystem
         S = S & TabStop & Drive.TotalSize
         S = S & TabStop & Drive.FreeSpace
         S = S & TabStop & Drive.AvailableSpace
         S = S & TabStop & Hex(Drive.SerialNumber)
      End If

      S = S & NewLine

   Next  

   GenerateDriveInformation = S

End Function

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' GenerateFileInformation
' 目的： 
' 生成一个字符串，来描述文件的当前状态。
' 示范下面的内容
'  - File.Path
'  - File.Name
'  - File.Type
'  - File.DateCreated
'  - File.DateLastAccessed
'  - File.DateLastModified
'  - File.Size
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Function GenerateFileInformation(File)

   Dim S

   S = NewLine & "Path:" & TabStop & File.Path
   S = S & NewLine & "Name:" & TabStop & File.Name
   S = S & NewLine & "Type:" & TabStop & File.Type
   S = S & NewLine & "Attribs:" & TabStop & ShowFileAttr(File)
   S = S & NewLine & "Created:" & TabStop & File.DateCreated
   S = S & NewLine & "Accessed:" & TabStop & File.DateLastAccessed
   S = S & NewLine & "Modified:" & TabStop & File.DateLastModified
   S = S & NewLine & "Size" & TabStop & File.Size & NewLine

   GenerateFileInformation = S

End Function

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' GenerateFolderInformation
' 目的： 
' 生成一个字符串，来描述文件夹的当前状态。
' 示范下面的内容
'  - Folder.Path
'  - Folder.Name
'  - Folder.DateCreated
'  - Folder.DateLastAccessed
'  - Folder.DateLastModified
'  - Folder.Size
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Function GenerateFolderInformation(Folder)

   Dim S

   S = "Path:" & TabStop & Folder.Path
   S = S & NewLine & "Name:" & TabStop & Folder.Name
   S = S & NewLine & "Attribs:" & TabStop & ShowFileAttr(Folder)
   S = S & NewLine & "Created:" & TabStop & Folder.DateCreated
   S = S & NewLine & "Accessed:" & TabStop & Folder.DateLastAccessed
   S = S & NewLine & "Modified:" & TabStop & Folder.DateLastModified
   S = S & NewLine & "Size:" & TabStop & Folder.Size & NewLine

   GenerateFolderInformation = S

End Function

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' GenerateAllFolderInformation
' 目的： 
' 生成一个字符串，来描述一个文件夹和所有文件及子文件夹的当前状态。
' 示范下面的内容
'  - Folder.Path
'  - Folder.SubFolders
'  - Folders.Count
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Function GenerateAllFolderInformation(Folder)

   Dim S
   Dim SubFolders
   Dim SubFolder
   Dim Files
   Dim File

   S = "Folder:" & TabStop & Folder.Path & NewLine & NewLine
   Set Files = Folder.Files

   If 1 = Files.Count Then
      S = S & "There is 1 file" & NewLine
   Else
      S = S & "There are " & Files.Count & " files" & NewLine
   End If

   If Files.Count <> 0 Then
      For Each File In Files
         S = S & GenerateFileInformation(File)
      Next
   End If

   Set SubFolders = Folder.SubFolders

   If 1 = SubFolders.Count Then
      S = S & NewLine & "There is 1 sub folder" & NewLine & NewLine
   Else
      S = S & NewLine & "There are " & SubFolders.Count & " sub folders" & NewLine & NewLine
   End If

   If SubFolders.Count <> 0 Then
      For Each SubFolder In SubFolders
         S = S & GenerateFolderInformation(SubFolder)
      Next
      S = S & NewLine
      For Each SubFolder In SubFolders
         S = S & GenerateAllFolderInformation(SubFolder)
      Next
   End If

   GenerateAllFolderInformation = S

End Function

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' GenerateTestInformation
' 目的： 
' 生成一个字符串，来描述 C:\Test 文件夹和所有文件及子文件夹的当前状态。
' 示范下面的内容
'  - FileSystemObject.DriveExists
'  - FileSystemObject.FolderExists
'  - FileSystemObject.GetFolder
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Function GenerateTestInformation(FSO)

   Dim TestFolder
   Dim S

   If Not FSO.DriveExists(TestDrive) Then Exit Function
   If Not FSO.FolderExists(TestFilePath) Then Exit Function

   Set TestFolder = FSO.GetFolder(TestFilePath)

   GenerateTestInformation = GenerateAllFolderInformation(TestFolder) 

End Function

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' DeleteTestDirectory
' 目的： 
' 清理 test 目录。
' 示范下面的内容
'  - FileSystemObject.GetFolder
'  - FileSystemObject.DeleteFile
'  - FileSystemObject.DeleteFolder
'  - Folder.Delete
'  - File.Delete
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Sub DeleteTestDirectory(FSO)

   Dim TestFolder
   Dim SubFolder
   Dim File
   
   ' 有两种方法可用来删除文件：

   FSO.DeleteFile(TestFilePath & "\Beatles\OctopusGarden.txt")

   Set File = FSO.GetFile(TestFilePath & "\Beatles\BathroomWindow.txt")
   File.Delete   

   ' 有两种方法可用来删除文件夹：
   FSO.DeleteFolder(TestFilePath & "\Beatles")
   FSO.DeleteFile(TestFilePath & "\ReadMe.txt")
   Set TestFolder = FSO.GetFolder(TestFilePath)
   TestFolder.Delete

End Sub

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' CreateLyrics
' 目的： 
' 在文件夹中创建两个文本文件。
' 示范下面的内容
'  - FileSystemObject.CreateTextFile
'  - TextStream.WriteLine
'  - TextStream.Write
'  - TextStream.WriteBlankLines
'  - TextStream.Close
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Sub CreateLyrics(Folder)

   Dim TextStream
   
   Set TextStream = Folder.CreateTextFile("OctopusGarden.txt")
   
   TextStream.Write("Octopus' Garden ") ' 请注意，该语句不添加换行到文件中。
   TextStream.WriteLine("(by Ringo Starr)")
   TextStream.WriteBlankLines(1)
   TextStream.WriteLine("I'd like to be under the sea in an octopus' garden in the shade,")
   TextStream.WriteLine("He'd let us in, knows where we've been -- in his octopus' garden in the shade.")
   TextStream.WriteBlankLines(2)
   
   TextStream.Close

   Set TextStream = Folder.CreateTextFile("BathroomWindow.txt")
   TextStream.WriteLine("She Came In Through The Bathroom Window (by Lennon/McCartney)")
   TextStream.WriteLine("")
   TextStream.WriteLine("She came in through the bathroom window protected by a silver spoon")
   TextStream.WriteLine("But now she sucks her thumb and wanders by the banks of her own lagoon")
   TextStream.WriteBlankLines(2)
   TextStream.Close

End Sub

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' GetLyrics
' 目的： 
' 显示 lyrics 文件的内容。
' 示范下面的内容
'  - FileSystemObject.OpenTextFile
'  - FileSystemObject.GetFile
'  - TextStream.ReadAll
'  - TextStream.Close
'  - File.OpenAsTextStream
'  - TextStream.AtEndOfStream
'  - TextStream.ReadLine
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Function GetLyrics(FSO)

   Dim TextStream
   Dim S
   Dim File

   ' 有多种方法可用来打开一个文本文件，和多种方法来从文件读取数据。
   ' 这儿用了两种方法来打开文件和读取文件：

   Set TextStream = FSO.OpenTextFile(TestFilePath & "\Beatles\OctopusGarden.txt", OpenFileForReading)
   
   S = TextStream.ReadAll & NewLine & NewLine
   TextStream.Close

   Set File = FSO.GetFile(TestFilePath & "\Beatles\BathroomWindow.txt")
   Set TextStream = File.OpenAsTextStream(OpenFileForReading)
   Do    While Not TextStream.AtEndOfStream
      S = S & TextStream.ReadLine & NewLine
   Loop
   TextStream.Close

   GetLyrics = S
   
End Function

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' BuildTestDirectory
' 目的： 
' 创建一个目录分层结构来示范 FileSystemObject。
' 以这样的次序来创建分层结构：
' C:\Test
' C:\Test\ReadMe.txt
' C:\Test\Beatles
' C:\Test\Beatles\OctopusGarden.txt
' C:\Test\Beatles\BathroomWindow.txt
' 示范下面的内容
'  - FileSystemObject.DriveExists
'  - FileSystemObject.FolderExists
'  - FileSystemObject.CreateFolder
'  - FileSystemObject.CreateTextFile
'  - Folders.Add
'  - Folder.CreateTextFile
'  - TextStream.WriteLine
'  - TextStream.Close
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Function BuildTestDirectory(FSO)

   Dim TestFolder
   Dim SubFolders
   Dim SubFolder
   Dim TextStream
   ' 排除(a)驱动器不存在，或(b)要创建的目录已经存在的情况。

   If Not FSO.DriveExists(TestDrive) Then
      BuildTestDirectory = False
      Exit Function
   End If

   If FSO.FolderExists(TestFilePath) Then
      BuildTestDirectory = False
      Exit Function
   End If

   Set TestFolder = FSO.CreateFolder(TestFilePath)

   Set TextStream = FSO.CreateTextFile(TestFilePath & "\ReadMe.txt")
   TextStream.WriteLine("My song lyrics collection")
   TextStream.Close

   Set SubFolders = TestFolder.SubFolders
   Set SubFolder = SubFolders.Add("Beatles")
   CreateLyrics SubFolder   
   BuildTestDirectory = True

End Function

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' 主程序
' 首先，它创建一个 test 目录，以及一些子文件夹和文件。 
' 然后，它转储有关可用磁盘驱动器和 test 目录的某些信息，
' 最后，清除 test 目录及其所有内容。
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Sub Main

   Dim FSO

   ' 设立全局变量。
   TabStop = Chr(9)
   NewLine = Chr(10)
   
   Set FSO = CreateObject("Scripting.FileSystemObject")

   If Not BuildTestDirectory(FSO) Then 
      Print "Test directory already exists or cannot be created.  Cannot continue."
      Exit Sub
   End If

   Print GenerateDriveInformation(FSO) & NewLine & NewLine
   Print GenerateTestInformation(FSO) & NewLine & NewLine
   Print GetLyrics(FSO) & NewLine & NewLine
   DeleteTestDirectory(FSO)

End Sub
© 2000 Microsoft Corporation 版权所有。保留所有权利。使用规定。
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